Catalyst Compositions and Their Use in Aromatic Alkylation Processes

ABSTRACT

Catalyst composition which comprises a first zeolite having a BEA* framework type and a second zeolite having a MOR framework type and a mesopore surface area of greater than 30 m2/g is disclosed. These catalyst compositions are used to remove catalyst poisons from untreated feed streams having one or more impurities which cause deactivation of the downstream catalysts employed in hydrocarbon conversion processes, such as those that produce mono-alkylated aromatic compounds.

PRIORITY CLAIM

This application claims priority to and the benefit of U.S. ProvisionalApplication No. 62/464,713, filed Feb. 28, 2017, and EP 17169516.6 whichwas filed May 4, 2017, the disclosures of which are both incorporatedherein by their reference.

FIELD OF THE INVENTION

This invention relates to catalyst compositions having an increasedcapacity to adsorb catalyst poisons from hydrocarbon streams. Thisinvention also relates to the use of the catalyst compositions to removesuch catalyst poisons from untreated feed streams having one or moreimpurities which cause deactivation of the downstream catalysts employedin hydrocarbon conversion processes, such as those that producemono-alkylated aromatic compounds. As a result, the cycle length of suchcatalyst is increased.

BACKGROUND OF THE INVENTION

In a typical aromatic alkylation process, an aromatic compound isreacted with an alkylating agent, such as an olefin, in the presence ofacid catalyst. For example, benzene can be reacted with ethylene orpropylene to produce ethylbenzene or cumene, both of which are importantintermediates in the chemical industry. In the past, commercial aromaticalkylation processes normally used AlCl₃ or BF₃ as the acid catalyst,but more recently these materials have been replaced by molecularsieve-based catalysts.

Aromatics alkylation processes employing molecular sieve-based catalystsmay be conducted in either the vapor phase or the liquid phase. However,in view of the improved selectivity and decreased capital and operatingcosts associated with liquid phase operation, most commercial alkylationprocesses now operate under at least partial liquid phase conditions.Unfortunately, one disadvantage of operating under liquid phaseconditions is that the molecular sieve-based catalysts tend to be moresensitive to the presence of catalyst poisons in the feed streams,especially those with a compound having at least one of the followingelements: nitrogen, halogens, oxygen, sulfur, arsenic, selenium,tellurium, phosphorus, and Group 1 through Group 12 metals. Suchimpurities reduce the acid activity of such molecular sieve-basedcatalyst and hence decrease the cycle time between requiredregenerations of such catalyst.

The use of guard beds to remove trace contaminants from hydrocarbon feedstreams is well known in the art. This is especially true forpetrochemical and specialty chemical operations where product purity iscritical. Normally, guard bed materials that contain bentonite clay,kaolin clay, special activated aluminas or molecular sieves are used andare placed upstream of a reaction vessel containing an acidic molecularsieve-based catalyst. These guard bed materials trap impurities in thefeed streams so that product purity specifications can be met andpoisoning of such catalyst can be reduced. However, such guard bedmaterials have limited capacity to adsorb impurities from aromatic feedstreams to the low levels required for use in liquid phase alkylationprocesses which employ acidic molecular sieve-based catalysts.Therefore, a need exists for a guard bed material with an increasedcapacity to adsorb impurities more effectively. It is desirable toremove such impurities from the feed streams to such aromatic alkylationprocesses and thereby reduce the deactivation of the downstream acidicmolecular sieve-based catalyst used in alkylation and/or transalkylationreactions.

SUMMARY OF THE INVENTION

It has now been found that the catalyst compositions of this inventionhave an improved capacity to adsorb catalyst poisons from hydrocarbonstreams, particularly feed streams to processess to producemono-alkylated aromatic compounds, such as benzene and ethylene, usingzeolite-based alkylation catalysts, thereby increasing the cycle lengthof such alkylation catalysts.

In a first aspect, this invention is a catalyst composition comprising afirst zeolite having a BEA* framework type and a second zeolite having aMOR framework type. The first zeolite can be zeolite beta. The secondzeolite can be any one of TEA-mordenite, EMM-34, UZM-14 or combinationsof two or more thereof. Also, the second zeolite can be a naturalmordenite or mordenite synthesized with sodium (Na) only, (Na)Mordenite.

EMM-34 has a mesopore surface area of greater than 30 m²/g andcomprising agglomerates composed of primary crystallites, wherein theprimary crystallites have an average primary crystal size as measured byTEM of less than 80 nm, an aspect ratio of less than 2 and a totalsurface area of greater than 500 m²/g. In some embodiments, EMM-34 has aratio of the mesopore surface area to the total surface area of greaterthan 0.05, and is synthesized from TEA or MTEA.

The ratio of the first zeolite to the second zeolite of the catalystcomposition is in the range of 90:10 to 50:50 by weight of the catalystcomposition. The Si/Al₂ molar ratio of the second zeolite of thecatalyst composition is in the range of 10 to 60. The collidine uptakeof the catalyst composition can be in the range of 550 μmoles/g to 1500μmoles/g, or in the range of 550 μmoles/g to 700 μmoles/g.

The catalyst composition of this invention can be made by a method suchthat the first zeolite and the second zeolite are co-crystallized in thesame synthesis mixture. The catalyst composition can be made by a methodsuch that the first zeolite and the second zeolite are co-extruded.

In a second aspect, this invention is a method for removing impuritiesfrom a hydrocarbon stream. The method comprises step (a) of supplying afeed stream and a guard bed catalyst. The feed stream comprises one ormore hydrocarbons and undesirable impurities. The impurities comprise atleast one compound having at least one of the following elements:nitrogen, halogens, oxygen, sulfur, arsenic, selenium, tellurium,phosphorus, and Group 1 through Group 12 metals. The guard bed catalystcomprises any one of the catalyst composition of this invention,described herein. In step (b) of the method, at least a portion of thefeed stream is contacted with the guard bed catalyst to remove at leasta portion of the impurities and produce a treated feed stream having areduced amount of impurities. In one or more embodiments, the feedstream and the guard bed are supplied to a guard bed for contactingtherein.

In a third aspect, this invention is a process for producing amono-alkylated aromatic compound. The process comprises step (a) ofproviding a guard bed having a guard bed catalyst disposed therein. Theguard bed catalyst comprises any one of the catalyst compositions ofthis invention. In step (b), at least a portion of an untreated feedstream is supplied to the guard bed. The untreated feed stream comprisesan alkylatable aromatic compound and undesirable impurities, as definedherein. In step (c), the portion of the untreated feed stream of step(b) is contacted with the guard bed catalyst to remove at least aportion of the impurities and produce a treated feed stream having areduced amount of impurities. In step (d), at least a portion of thetreated feed stream of step (b) and an alkylating agent stream iscontacted with an alkylation catalyst which is the same or differentfrom the guard bed catalyst under suitable at least partially liquidphase reaction conditions to alkylate at least a portion of thealkylatable aromatic compound with the alkylating agent stream toproduce an effluent stream. The effluent stream comprises themono-alkylated aromatic compound and poly-alkylated aromatic compounds.

In one or more embodiments, the alkylation catalyst comprises an acidicaluminosilicate. The aluminosilicate can or is any one of a MCM-22family molecular sieve, faujasite, mordenite, zeolite beta, orcombinations of two or more thereof.

In one or more embodiments, the process further comprises one or moreseparation steps to recover a mono-alkylated aromatic compound streamand a poly-alkylated aromatic compounds stream.

In one or more embodiments, the process further comprises atransalkylation step of contacting the poly-alkylated aromatic compoundstream and another portion of the feed stream of step (a) with atransalkylation catalyst under suitable at least partially liquid phasetransalkylation conditions to transalkylate the poly-alkylated aromaticcompound stream with the alkylatable aromatic compound and produceadditional the mono-alkylated aromatic compound. In one or moreembodiments, the transalkylation catalyst is a large pore molecularsieve having a Constraint Index of less than 2. In other embodiments,the transalkylation catalyst is a MCM-22 family material. In one or moreembodiments, the portion of the feed stream of step (a) fortransalkylation is first contacted with a guard bed catalyst of thisinvention to remove at least of a portion of impurities.

When the alkylatable aromatic compound is benzene and the alkylatingagent is ethylene, the mono-alkylated aromatic compound is ethylbenzeneand the poly-alkylated aromatic compound is poly-ethylbenzene. When thealkylatable aromatic compound is benzene and the alkylating agent ispropylene, the mono-alkylated aromatic compound is cumene and thepoly-alkylated aromatic compound is poly-isopropylbenzene.

In one or more embodiments of the process, step (b) further includessupplying an alkylating agent stream to the guard bed in addition to thefeed stream which comprises the alkylatable aromatic compound andundesirable impurities. In one or more embodiments, step (c) furtherincludes contacting the alkylating agent stream with the alkylatablearomatic compound in the presence of the guard bed catalyst to produceadditional mono-alkylated aromatic compound. When operated as such, theguard bed is referred to as a reactive guard bed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the performance of the catalyst compositions of Example 5as measured by the Alpha Value plotted as a function of the zeolitebeta, EMM-34 or TEA-mordenite content of the catalyst composition.

FIG. 2 shows the performance of the catalyst compositions of Example 6as measured by collidine uptake plotted as a function of the zeolitebeta, EMM-34 or TEA-mordenite content of the catalyst composition.

FIG. 3 shows the performance of the catalyst compositions of Example 7as measured by Temperature Programmed Ammonia Desorption as a functionof the zeolite beta, EMM-34 or TEA-mordenite content of the catalystcomposition.

FIG. 4 is the X-ray diffraction pattern for Example 8.

FIG. 5 is the X-ray diffraction pattern for Example 9.

FIG. 6 is the X-ray diffraction pattern for Example 10.

FIG. 7 is the X-ray diffraction pattern for Example 11.

DETAILED DESCRIPTION OF THE INVENTION

Increased capacity to adsorb catalyst poisons from hydrocarbons streamsis to exhibited by the catalyst composition of this invention, describedherein, when used in a process for producing a mono-alkylated aromaticcompound, preferably ethylbenzene or cumene, by the alkylation ofalkylatable aromatic compound, preferably benzene, with an with analkylating agent, preferably ethylene or propylene, in the presence ofsuch composition under at least partial liquid phase conditions.

Definitions

The term “catalyst compound” as used herein, includes a material thatcan act to increase the rate constant in a chemical reaction, as well asa material that can act to adsorb catalyst poisons from a hydrocarbonstream.

The term “alkylatable aromatic compound” as used herein, means anaromatic compound that may receive an alkyl group. One non-limitingexample of an alkylatable aromatic compound is benzene.

The term “alkylating agent” as used herein, means a compound which maydonate an alkyl group to an alkylatable aromatic compound. Non-limitingexamples of an alkylating agent are ethylene, propylene, and butylene.Another non-limiting example is any poly-alkylated aromatic compoundthat is capable of donating an alkyl group to an alkylatable aromaticcompound.

The term “aromatic” as used herein, in reference to the alkylatablearomatic compounds which are useful herein, is to be understood inaccordance with its art-recognized scope which includes substituted andunsubstituted mono- and polynuclear compounds. Compounds of an aromaticcharacter which possess a heteroatom (e.g., N or S) are also usefulprovided they do not act as catalyst poisons, as defined below, underthe reaction conditions selected.

The term “at least partial liquid phase” as used herein, means a mixturehaving at least 1 wt. % liquid phase, optionally at least 5 wt. % liquidphase, at a given temperature, pressure, and composition.

The term “catalyst poisons” as used herein, means one or moreimpurities, defined herein, which acts to reduce the cycle-length of amolecular sieve or zeolite.

As used herein, the term “constraint index” is defined in U.S. Pat. Nos.3,972,832 and 4,016,218.

The term “framework type” as used herein has the meaning described inthe “Atlas of Zeolite Framework Types,” by Ch. Baerlocher, W. M. Meierand D. H. Olson (Elsevier, 5th Ed., 2001). The BEA* framework typeincludes various forms of zeolite beta. The MOR framework type includesvarious forms of mordenite such as, for example, TEA-mordenite, EMM-34and UZM-14.

Zeolite beta is described in U.S. Pat. No. 3,308,069 and U.S. ReissuePat. No. 28,341. Mordenite is a naturally occurring material but is alsoavailable in synthetic forms, such as TEA-mordenite (i.e., syntheticmordenite prepared from a reaction mixture comprising atetraethylammonium directing agent). TEA-mordenite is disclosed in U.S.Pat. Nos. 3,766,093 and 3,894,104. EMM-34, also referred to asmeso-mordenite, is a zeolite synthesized from structure directing agentsTEA (tetraethyl ammonium cation) or MTEA (methyl triethyl ammoniumcation) and having a mesopore surface area of greater than 30 m²/g andcomprising agglomerates composed of primary crystallites, wherein theprimary crystallites have an average primary crystal size as measured byTEM of less than 80 nm and an aspect ratio of less than 2, as disclosedin International Publication WO2016/126431, incorporated by referencewhere permitted. UZM-14 is described in U.S. Publication 20090325785 A1

The term “MCM-22 family material” (or “MCM-22 family molecular sieve”),as used herein, can include:

(i) molecular sieves made from a common first degree crystallinebuilding block “unit cell having the MWW framework topology.” A unitcell is a spatial arrangement of atoms which is tiled inthree-dimensional space to describe the crystal as described in the“Atlas of Zeolite Framework Types,” by Ch. Baerlocher, W. M. Meier andD. H. Olson (Elsevier, 5th Ed., 2001);

(ii) molecular sieves made from a common second degree building block, a2-dimensional tiling of such MWW framework type unit cells, forming a“monolayer of one unit cell thickness,” preferably one c-unit cellthickness;

(iii) molecular sieves made from common second degree building blocks,“layers of one or more than one unit cell thickness”, wherein the layerof more than one unit cell thickness is made from stacking, packing, orbinding at least two monolayers of one unit cell thick of unit cellshaving the MWW framework topology. The stacking of such second degreebuilding blocks can be in a regular fashion, an irregular fashion, arandom fashion, and any combination thereof; or

(iv) molecular sieves made by any regular or random 2-dimensional or3-dimensional combination of unit cells having the MWW frameworktopology.

The MCM-22 family materials are characterized by having an X-raydiffraction pattern including d-spacing maxima at 12.4±0.25, 3.57±0.07and 3.42±0.07 Angstroms (either calcined or as-synthesized). The MCM-22family materials may also be characterized by having an X-raydiffraction pattern including d-spacing maxima at 12.4±0.25, 6.9±0.15,3.57±0.07 and 3.42±0.07 Angstroms (either calcined or as-synthesized).The X-ray diffraction data used to characterize the molecular sieve areobtained by standard techniques using the K-alpha doublet of copper asthe incident radiation and a diffractometer equipped with ascintillation counter and associated computer as the collection system.

Members of the MCM-22 family include, but are not limited to, MCM-22(described in U.S. Pat. No. 4,954,325), PSH-3 (described in U.S. Pat.No. 4,439,409), SSZ-25 (described in U.S. Pat. No. 4,826,667), ERB-1(described in European Patent 0293032), ITQ-1 (described in U.S. Pat.No. 6,077,498), ITQ-2 (described in International Patent Publication No.WO97/17290), ITQ-30 (described in International Patent Publication No.WO2005118476), MCM-36 (described in U.S. Pat. No. 5,250,277), MCM-49(described in U.S. Pat. No. 5,236,575), MCM-56 (described in U.S. Pat.No. 5,362,697; and an EMM-10 family molecular sieve (described orcharacterized in U.S. Pat. Nos. 7,959,899 and 8,110,176; and U.S. PatentApplication Publication No. 2008/0045768), such as EMM-10, EMM-10-P,EMM-12 and EMM-13. Typically, the molecular sieve of the MCM-22 familyis in the hydrogen form and having hydrogen ions, for example, acidic.

Related zeolites to be included in the MCM-22 family are UZM-8(described in U.S. Pat. No. 6,756,030), UZM-8HS (described in U.S. Pat.No. 7,713,513), UZM-37 (described in U.S. Pat. No. 8,158,105), and MIT-1is described in Chem. Sci., 2015, 6, 6320-6324, all of which are alsosuitable for use as the molecular sieve of the MCM-22 family.

The term “hydrocarbon” means a class of compounds containing hydrogenbound to carbon, and encompasses (i) saturated hydrocarbon compounds,(ii) unsaturated hydrocarbon compounds, and (iii) mixtures ofhydrocarbon compounds (saturated and/or unsaturated), including mixturesof hydrocarbon compounds having different values of n, where n is thenumber of carbon atom(s) per molecule.

The term “mono-alkylated aromatic compound” means an aromatic compoundthat has only one alkyl substituent. Non-limiting examples ofmono-alkylated aromatic compounds are ethylbenzene, iso-propylbenzene(cumene) and sec-butylbenzene.

The term “poly-alkylated aromatic compound” as used herein, means anaromatic compound that has more than one alkyl substituent. Anon-limiting example of a poly-alkylated aromatic compound ispoly-ethylbenzene, e.g., di-ethylbenzene, tri-ethylbenzene, andpoly-isopropylbenzene, e.g., di-isopropylbenzene, andtri-isopropylbenzene.

The term “impurities” as used herein, includes, but is not limited to,compounds having at least one of the following elements: nitrogen,halogens, oxygen, sulfur, arsenic, selenium, tellurium, phosphorus, andGroup 1 through Group 12 metals.

The term “large pore molecular sieve” as used herein, means molecularsieve having a Constraint Index of less than 2.

Suitable large pore molecular sieves include zeolite beta, zeolite Y,Ultrastable Y (USY), Dealuminized Y (Deal Y), Ultrahydrophobic Y(UHP-Y), Rare earth exchanged Y (REY), mordenite, TEA-mordenite, ZSM-2,ZSM-3, ZSM-4, ZSM-14, ZSM-18 and ZSM-20. Zeolite ZSM-2 is described inU.S. Pat. No. 3,411,874. Zeolite ZSM-3 is described in U.S. Pat. No.3,415,736. ZSM-4 is described in U.S. Pat. No. 4,021,447. ZSM-14 isdescribed in U.S. Pat. No. 3,923,636. ZSM-18 is described in U.S. Pat.No. 3,950,496. Zeolite ZSM-20 is described in U.S. Pat. No. 3,972,983.Low sodium Ultrastable Y molecular sieve (USY) is described in U.S. Pat.Nos. 3,293,192 and 3,449,070. Dealuminized Y zeolite (Deal Y) may beprepared by the method found in U.S. Pat. No. 3,442,795.Ultrahydrophobic Y (UHP-Y) is described in U.S. Pat. No. 4,401,556. Rareearth exchanged Y (REY) is described in U.S. Pat. No. 3,524,820. ECR-4is described in U.S. Pat. No. 4,965,059. ECR-17 is described in EPPublication EP0259526. ECR-32 is described in U.S. Pat. No. 4,931,267.ECR-35 is described in U.S. Pat. No. 5,116,590.

The term “comprising” (and its grammatical variations) as used herein,is used in the inclusive sense of “having” or “including” and not in theexclusive sense of “consisting only of” The terms “a” and “the” as usedherein are understood to encompass the plural as well as the singular.

The entire contents of each and every aforementioned patents andpublications are incorporated herein by reference in their entireties.

Catalyst Composition

The first aspect of this invention is a catalyst composition whichcomprises a first zeolite having a BEA* framework type and a secondzeolite having a MOR framework type. The first zeolite can be zeolitebeta. The second zeolite can be any one of TEA-mordenite, EMM-34, UZM-14or combinations of two or more thereof. TEA-mordenite, EMM-34 and UZM-14are described in the publications, referenced above.

In one or more embodiments, EMM-34 has a mesopore surface area ofgreater than 30 m²/g (as measured by BET) and comprising agglomeratescomposed of primary crystallites, wherein the primary crystallites havean average primary crystal size as measured by TEM of less than 80 nm,an aspect ratio of less than 2 and a total surface area of greater than500 m²/g (as measured by BET)

In some embodiments, EMM-34 has a ratio of the mesopore surface area tothe total surface area of greater than 0.05, and is synthesized from TEAor MTEA.

The EMM-34 has a mesopore surface area as measured by BET of greaterthan 30 m²/g, preferably greater than 40 m²/g, and in some cases greaterthan 45 m²/g.

EMM-34 comprises agglomerates, typically irregular agglomerates, whichare composed of primary crystallites which have an average primarycrystal size as measured by TEM of less than 80 nm, preferably less than70 nm and more preferably less than 60 nm, for example, less than 50 nm.The primary crystallites may have an average primary crystal size in therange of greater than 20 nm, optionally greater than 30 nm to less than80 nm as measured by TEM.

Optionally, the primary crystals of EMM-34 have an average primarycrystal size of less than 80 nm, preferably less than 70 nm, and in somecases less than 60 nm, in each of the a, b and c crystal vectors asmeasured by X-ray diffraction. The primary crystallites may optionallyhave an average primary crystal size in the range of greater than 20 nm,optionally greater than 30 nm to less than 80 nm, in each of the a, band c crystal vectors, as measured by X-ray diffraction.

EMM-34 will generally comprise a mixture of agglomerates of the primarycrystals together with some unagglomerated primary crystals. Themajority of EMM-34, for example, greater than 80 weight % or greaterthan 90 weight %, will be present as agglomerates of primary crystals.The agglomerates are typically of irregular form. For more informationon agglomerates please see Walter, D. (2013) PrimaryParticles—Agglomerates—Aggregates, in Nanomaterials (ed DeutscheForschungsgemeinschaft (DFG)), Wiley-VCH Verlag GmbH & Co. KGaA,Weinheim, Germany. doi: 10.1002/9783527673919, pages 1-24. Usefully,EMM-34 is not an aggregate.

Optionally, EMM-34 comprises at least 50% by weight, preferably at least70% by weight, advantageously at least 80% by weight, more preferably atleast 90% by weight and optionally substantially consists of theirregular agglomerates composed of primary crystallites having a primarycrystal size of less than 80 nm, preferably less than 70 nm, and morepreferably less than 60 nm, for example, less than 50 nm. Preferably,EMM-34 comprises less than 10% by weight of primary crystallites havinga size of more than 80 nm as assessed by TEM. Preferably, EMM-34 iscomposed of the irregular agglomerates composed of crystallites having acrystal size as measured by TEM of less than 80 nm. Preferably, EMM-34of the invention is substantially free, for example, contains less than10% by number as assessed by TEM, of needle or platelet crystals.

Preferably, the primary crystallites of EMM-34 have an aspect ratio ofless than 3.0, more preferably less than 2.0, wherein the aspect ratiois defined as the longest dimension of the crystallite divided by thewidth of the crystallite, where the width of the crystallite is definedas the dimension of the crystallite in the middle of that longestdimension in a direction orthogonal to that longest dimension, asmeasured by TEM.

The agglomerates of the primary crystallites are typically of irregularform and may be referred to as being “secondary” particles because theyare formed of agglomerates of the crystallites, which are the “primary”particles.

The primary crystallites may have a narrow particle size distributionsuch that at least 90% of the primary crystallites by number have anaverage primary crystal size in the range of from 20 to 80 nm,preferably in the range of from 20 to 60 nm, as measured by TEM.

EMM-34 has a total surface area of greater than 500 m²/g, morepreferably greater than 550 m²/g, and in some cases greater than 600m²/g. The total surface area includes the surface area of the internalpores (zeolite surface area) and also the surface area on the outside ofthe crystals (the external surface area). The total surface area ismeasured by BET.

Preferably, the ratio of mesopore surface area to the total surface areafor EMM-34 is greater than 0.05.

EMM-34 has a mesopore volume of greater than 0.1 mL/g, more preferablygreater than 0.12 mL/g, and in some cases greater than 0.15 mL/g.

The silica-alumina molar ratio (Si:Al₂ molar ratio) of the secondzeolite, such as EMM-34, is preferably greater than 10 and may be in therange of, for example, from 10 to 60, preferably from 15 to 40.

The silica-alumina molar ratio (Si:Al₂ molar ratio) of the firstzeolite, such as zeolite beta, is preferably lower than 50 and may be inthe range of, for example, from 15 to 50, preferably from 15 to 25.

For the catalyst compositions of this invention, the ratio of the firstzeolite to the second zeolite is in the range of 90:10 to 50:50, or80:20 to 50:50, or 70:30 to 50:50, or 60:40 to 50:50 by weight of thecatalyst composition.

The Si/Al₂ molar ratio (silica-alumina molar ratio) of the secondzeolite of the catalyst composition, EMM-34 in some embodiments, is inthe range of 10 to 60 or 20 to 60 or 30 to 60.

The collidine uptake of the catalyst composition can greater than 500μmoles/g or in the range of 550 μmoles/g to 1500 μmoles/g, or in therange of 550 μmoles/g to 700 μmoles/g.

In one or more embodiments, the catalyst composition of this inventioncan be made by a method such the first zeolite and the second zeoliteare co-crystallized in the same synthesis mixture.

In one or more embodiments, the catalyst composition can be made by amethod such that the first zeolite is co-extruded with the secondzeolite. In this method, the first zeolite, such as zeolite beta, iscombined with the second zeolite, such as EMM-34, in a muller or a mixerand mixed for a period of time, such as 10 to 30 minutes. Sufficientwater is added to produce an extrudable paste which is then extrudedinto a shaped extrudate, such as in the shape of a cylinder orquadrulobe. The extrudate may then be dried at an elevated temperature,such as, for example, from 121° C. to 163° C. The dried extrudate maythen be calcined at high temperature, such as, for example, at 538° C.,under flowing air, nitrogen, a nitrogen/air mixture, or other gas. Thedried extrudate may then be cooled to ambient temperature, and may behumidified with saturated air or steam. After the humidification, theextrudate is typically ion exchanged with 0.5 to 1 N ammonium nitratesolution, for example, and then washed with deionized water, forexample, to remove residual ions, such as nitrate, for example, and thendried. The dried, exchanged extrudate is then calcined in air, nitrogen,a nitrogen/air mixture or other gas, at a temperature, for example,between 850° F. (454° C.) and 1100° F. (593° C.).

Method for Removing Impurities from Hydrocarbon Streams

The second aspect of this invention is a method for removing impuritiesfrom a hydrocarbon stream. The method comprises step (a) of providing aguard bed catalyst, preferably in a guard bed and having the guard bedcatalyst disposed therein. The guard bed catalyst comprises any one ofthe catalyst composition of this invention, described herein. In step(b) of the method, at least a portion of a feed stream is supplied tothe guard bed. The feed stream comprises one or more hydrocarbons andundesirable impurities. The impurities comprise at least one compoundhaving at least one of the following elements: nitrogen, halogens,oxygen, sulfur, arsenic, selenium, tellurium, phosphorus, and Group 1through Group 12 metals. In step (c) of the method, the portion of thefeed stream is contacted with the guard bed catalyst to remove at leasta portion of the impurities and produce a treated feed stream having areduced amount of impurities.

Process for Producing Mono-Alkylated Aromatic Compounds

The third aspect of this invention is a process for producing amono-alkylated aromatic compound. The process comprises step (a) ofproviding a guard bed catalyst, preferably, in a guard bed wherein theguard bed catalyst is disposed therein. The guard bed catalyst comprisesany one of the catalyst compositions of this invention. In step (b) ofthe process, at least a portion of an untreated feed stream is suppliedto the guard bed. In this step, the guard bed is a non-reactive guardbed because no alkylating agent is present. The untreated feed streamcomprises an alkylatable aromatic compound and undesirable impurities,as defined herein. Such impurities act as catalyst poisons to thedownstream alkylation catalyst and/or transalkylation catalyst, andthereby reduce the service life (e.g., cycle length) of these catalysts.In step (c) of the process, the portion of the untreated feed stream ofstep (b) is contacted with the guard bed catalyst to remove at least aportion of the impurities and produce a treated feed stream having areduced amount of impurities. In step (d) of the process, at least aportion of the treated feed stream having a reduced amount of impuritiesand an alkylating agent stream are contacted in the presence or with analkylation catalyst which is the same or different from the guard bedcatalyst. The contacting is under suitable at least partially liquidphase reaction conditions to alkylate at least a portion of thealkylatable aromatic compound with the alkylating agent stream toproduce an effluent stream. Such effluent stream comprises themono-alkylated aromatic compound and poly-alkylated aromatic compounds.The reduced amount of impurities in the treated feed stream subjects thedownstream alkylation and transalkylation catalysts to fewer catalystpoisons and enables longer service life for these downstream catalysts.

The step (b) can further include supplying an alkylating agent stream tothe guard bed. The alkylating agent stream is contacted with thealkylatable aromatic compound in the presence of the guard bed catalystto produce additional the mono-alkylated aromatic compound. In thisembodiment, the guard bed is a reactive guard bed in which an alkylatingagent stream is present. This results in an alkylated aromatic compoundbeing produced via an alkylation reaction between the alkylatablearomatic compound and alkylating agent and at the same time at least aportion of the impurities are removed from the feed stream viaadsorption by the guard bed catalyst.

The effluent stream of step (d) can be separated to recover amono-alkylated aromatic compound stream and a poly-alkylated aromaticcompounds stream in a step (e). The poly-alkylated aromatic compoundstream can be transalkylated with an alkylatable aromatic compound toproduce additional mono-alkylated aromatic compound in a step (f). Thisis done by contacting the poly-alkylated aromatic compound and anotherportion of the feed stream, such as the untreated feed stream of step(b), in the presence or with a transalkylation catalyst under suitableat least partially liquid phase transalkylation conditions totransalkylate the poly-alkylated aromatic compound stream with thealkylatable aromatic compound and produce additional the mono-alkylatedaromatic compound.

Alternatively, prior to step (f), the portion of the untreated feedstream is first contacted with a guard bed catalyst to remove at least aportion of the impurities to form a treated feed stream. The guard bedcatalyst comprises any one of the catalyst compositions of thisinvention.

In the embodiments of the invention, when the alkylatable aromaticcompound is benzene and the alkylating agent is propylene, themono-alkylated aromatic compound is ethylbenzene and the poly-alkylatedaromatic compound is poly-ethylbenzene.

In the embodiments of the invention, when the alkylatable aromaticcompound is benzene and the alkylating agent is ethylene, themono-alkylated aromatic compound is cumene and the poly-alkylatedaromatic compound is poly-isopropylbenzene.

Alkylation Catalyst and Transalkylation Catalyst

In one or more embodiments, the alkylation catalyst comprises analuminosilicate. The aluminosilicate is any one of a MCM-22 familymolecular sieve, faujasite, mordenite, zeolite beta, or combinations oftwo or more thereof, which has been found to be useful in processes forproduction of mono-alkylated aromatic compounds.

In one or more embodiments, the MCM-22 family molecular sieve isselected from the group consisting of MCM-22, MCM-36, MCM-49, MCM-56,ERB-1, EMM-10, EMM-10-P, EMM-12, EMM-13, UZM-8, UZM-8HS, UZM-37, ITQ-1,ITQ-2, ITQ-30, MIT-1, or combinations of two or more thereof.

In other embodiments, the transalkylation catalyst is a large poremolecular sieve having a constraint index of less than 2. The large poremolecular sieve is selected from the group of consisting of zeolitebeta, faujasite, mordenite, TEA-mordenite, EMM-34, ZSM-2, ZSM-3, ZSM-4,ZSM-14, ZSM-18, ZSM-20, ECR-4, ECR-17, ECR-32, ECR-35 and combinationsthereof. The faujasite large pore molecular sieve is selected from thegroup consisting of 13X, low sodium ultrastable Y (USY), dealuminized Y(Deal Y), ultrahydrophobic Y (UHP-Y), rare earth exchanged Y (REY), rareearth exchanged USY (RE-USY), and mixtures thereof.

The molecular sieve of the alkylation catalyst and/or thetransalkylation catalyst can be combined in conventional manner with anoxide binder, such as alumina or silica, such that the final alkylationcatalyst and/or transalkylation contains between 1 and 100 wt. % of themolecular sieve.

Alkylatable Aromatic Compounds

Substituted alkylatable aromatic compounds which can be alkylated hereinmust possess at least one hydrogen atom directly bonded to the aromaticnucleus. The aromatic rings can be substituted with one or more alkyl,aryl, alkaryl, alkoxy, aryloxy, cycloalkyl, halide, and/or other groupswhich do not interfere with the alkylation reaction.

Suitable alkylatable aromatic hydrocarbons for any one of theembodiments of this invention include benzene, naphthalene, anthracene,naphthacene, perylene, coronene, and phenanthrene, with benzene beingpreferred.

Generally the alkyl groups, which can be present as substituents on thearomatic compound, contain from 1 to about 22 carbon atoms and usuallyfrom about 1 to 8 carbon atoms, and most usually from about 1 to 4carbon atoms.

Suitable alkyl substituted aromatic compounds for any one of theembodiments of this invention include toluene, xylene, isopropylbenzene,normal propylbenzene, alpha-methylnaphthalene, ethylbenzene, cumene,mesitylene, durene, p-cymene, butylbenzene, pseudocumene,o-diethylbenzene, m-diethylbenzene, p-diethylbenzene, isoamylbenzene,isohexylbenzene, pentaethylbenzene, pentamethylbenzene;1,2,3,4-tetraethylbenzene; 1,2,3,5-tetramethylbenzene;1,2,4-triethylbenzene; 1,2,3-trimethylbenzene, m-butyltoluene;p-butyltoluene; 3,5-diethyltoluene; o-ethyltoluene; p-ethyltoluene;m-propyltoluene; 4-ethyl-m-xylene; dimethylnaphthalene;ethylnaphthalene; 2,3-dimethylanthracene; 9-ethylanthracene;2-methylanthracene; o-methylanthracene; 9,10-dimethylphenanthrene; and3-methyl-phenanthrene. Higher molecular weight alkylaromatichydrocarbons can also be used as starting materials and include aromatichydrocarbons such as are produced by the alkylation of aromatichydrocarbons with olefin oligomers. Such products are frequentlyreferred to in the art as alkylate and include hexylbenzene,nonylbenzene, dodecylbenzene, pentadecylbenzene, hexyltoluene,nonyltoluene, dodecyltoluene, pentadecyltoluene, etc. Very oftenalkylate is obtained as a high boiling fraction in which the alkyl groupattached to the aromatic nucleus varies in size from about C₆ to aboutC₁₂. When cumene or ethylbenzene is the desired product, the presentprocess produces acceptably little by-products such as xylenes. Thexylenes made in such instances may be less than about 500 ppm.

Reformate containing substantial quantities of benzene, toluene and/orxylene constitutes a useful feed for the process of this invention.

Alkylating Agents

The alkylating agents, which are useful in one or more embodiments ofthis invention, generally include any aliphatic or aromatic organiccompound having one or more available alkylating olefinic groups capableof reaction with the alkylatable aromatic compound, preferably with thealkylating group possessing from 1 to 5 carbon atoms, or poly-alkylatedaromatics compound(s). Examples of suitable alkylating agents for anyone of the embodiments of this invention are olefins such as ethylene,propylene, the butenes, and the pentenes; alcohols (inclusive ofmonoalcohols, dialcohols, trialcohols, etc.), such as methanol, ethanol,the propanols, the butanols, and the pentanols; aldehydes such asformaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, andn-valeraldehyde; and alkyl halides such as methyl chloride, ethylchloride, the propyl chlorides, the butyl chlorides, and the pentylchlorides, and so forth.

Mixtures of light olefins are especially useful as alkylating agents inthe alkylation process of this invention. Accordingly, mixtures ofethylene, propylene, butenes, and/or pentenes which are majorconstituents of a variety of refinery streams, e.g., fuel gas, gas plantoff-gas containing ethylene, propylene, etc., naphtha cracker off-gascontaining light olefins, refinery FCC propane/propylene streams, etc.,are useful alkylating agents herein.

Poly-alkylated aromatic compounds suitable for one or more embodimentsof this invention include, but are not limited to, polyethylbenzene(s),polyisporpoylebenzene(s) or mixtures thereof.

For example, a typical FCC light olefin stream possesses the followingcomposition as shown in Table I:

TABLE I Wt. % Mol. % Ethane 3.3 5.1 Ethylene 0.7 1.2 Propane 14.5 15.3Propylene 42.5 46.8 Isobutane 12.9 10.3 n-butane 3.3 2.6 Butenes 22.118.32 Pentanes 0.7 0.4Alkylation and/or Transalkylation Conditions

In one or more embodiments, the alkylation and/or transalkylationprocesses of this invention is conducted such that the organicreactants, i.e., the alkylatable aromatic compound and the alkylatingagent, are brought into contact with an alkylation or transalkylationcatalyst in a suitable alkylation or transalkylation reaction zone suchas, for example, in a flow reactor containing a fixed bed of thecatalyst composition, under effective and suitable alkylation and/ortransalkylation conditions.

Such alkylation conditions can include at least one of the following: atemperature of from about 10° C. and about 400° C., or from about 10° C.to about 200° C., or from about 150° C. to about 300° C., a pressure upto about 25000 kPa, or up to about 20000 kPa, or from about 100 kPa toabout 7000 kPa, or from about 689 kPa to about 4601 kPa, a molar ratioof alkylatable aromatic compound to alkylating agent of from about 0.1:1to about 50:1, preferably from about 0.5:1 to 10:1, and a feed weighthourly space velocity (WHSV) of between about 0.1 and about 100 hr⁻¹, orfrom about 0.5 to 50 hr⁻¹, or from about 10 hr⁻¹ to about 100 hr⁻¹.

The reactants can be in either the vapor phase or in the liquid phase,or in the at least partially liquid phase. In one or more embodiments,the reactants can be neat, i.e., free from intentional admixture ordilution with other material, or they can include carrier gases ordiluents such as, for example, hydrogen or nitrogen.

When benzene is alkylated with ethylene to produce ethylbenzene, thealkylation reaction may be carried out under at least partially liquidphase conditions including a temperature between about 150° C. and 300°C., or between about 200° C. and 260° C., a pressure up to about 20000kPa, preferably from about 200 kPa to about 5600 kPa, a WHSV of fromabout 0.1 hr⁻¹ to about 50 hr⁻¹, or from about 1 hr⁻¹ and about 10 hr⁻¹based on the ethylene feed, and a ratio of the benzene to the ethylenein the alkylation reactor from 1:1 to 30:1 molar, preferably from about1:1 to 10:1 molar.

When benzene is alkylated with propylene to produce cumene, the reactionmay be carried out under at least partially liquid phase conditionsincluding a temperature of up to about 250° C., preferably from about10° C. to about 200° C.; a pressure up to about 25000 kPa, preferablyfrom about 100 kPa to about 3000 kPa; and a WHSV of from about 1 hr⁻¹ toabout 250 hr⁻¹, preferably from 5 hr⁻¹ to 50 hr⁻¹, preferably from about5 hr⁻¹ to about 10 hr⁻¹ based on the ethylene feed.

Such transalkylation conditions can include at least one of thefollowing: a temperature of about 100° C. to about 300° C., or fromabout 100° C. to about 275° C., a pressure of about 200 kPa to about 600kPa, or about 200 kPa to about 500 kPa, a weight hourly space velocity(WHSV) based on the total feed of about 0.5 hr⁻¹ to about 100 hr⁻¹ ontotal feed, and aromatic/poly-alkylated aromatic compound weight ratio1:1 to 6:1.

When the poly-alkylated aromatic compounds are polyethylbenzenes and arereacted with benzene to produce ethylbenzene, the transalkylationconditions include a temperature of from about 220° C. to about 260° C.,a pressure of from about 300 kPa to about 400 kPa, weight hourly spacevelocity of 2 to 6 on total feed and benzene/PEB weight ratio 2:1 to6:1.

When the poly-alkylated aromatic compounds are poly-isopropylbenzenes(PIPBs) and are reacted with benzene to produce cumene, thetransalkylation conditions include a temperature of from about 100° C.to about 200° C., a pressure of from about 300 kPa to about 400 kPa, aweight hourly space velocity of 1 to 10 on total feed and benzene/PIPBweight ratio 1:1 to 6:1.

EXAMPLES

The invention will now be more particularly described with reference tothe following Examples. Numerous modifications and variations arepossible and it is to be understood that within the scope of theappended claims, the invention may be practiced otherwise than asspecifically described herein.

EXPERIMENTAL Alpha Value

The alpha value is a measure of the cracking activity of a catalystcomposition and is described in U.S. Pat. No. 3,354,078 and in theJournal of Catalysis, Vol. 4, p. 527 (1965); Vol. 6, p. 278 (1966) andVol. 61, p. 395 (1980), each incorporated herein by reference. Theexperimental conditions of the test used herein included a constanttemperature of 538° C. and a variable flow rate as described in detailin the Journal of Catalysis, Vol. 61, p. 395 (1980).

Collidine Uptake

Collidine uptake is a measure of the acidity of a zeolite or catalystcomposition. The collidine uptake of the zeolites and catalystcompositions was determined as the millimoles of collidine (a type ofcatalyst poison) absorbed per gram of a zeolite or catalyst compositionsample that is dried under nitrogen flow at 200° C. for 60 minutes on aThermogravametric Analyzer (Model Q5000, manufactured by TA Instruments,New Castle, Del.). After drying the catalyst sample, the collidine (as acatalyst poison) was sparged over the catalyst sample for 60 minutes ata collidine partial pressure of 3 torr. The collidine uptake wascalculated from the following formula: (catalyst sample weight aftersparging with collidine−dried catalyst sample weight)×106÷(molecularweight of collidine×dried catalyst sample weight). When the catalystsample weight and the dried catalyst sample weight is measured in grams,the molecular weight of collidine is 121.2 grams per millimole.

Temperature Programmed Ammonia Desorption

Temperature programmed ammonia desorption (TPAD) is also a measure ofthe acidity of a zeolite or catalyst composition. TPAD techniques arewell known in the art. For the TPAD analysis, a catalyst sample (0.2 g)was first dried at 500° C. for 3 hours under a helium (He) flow rate of10 cc/min. The temperature was then reduced to 100° C. whereupon thecatalyst sample was saturated with ammonia gas. After saturation withammonia gas, the catalyst sample was desorbed at 100° C. with heliumflow to desorb physisorbed ammonia from the catalyst sample. TPAD wasperformed at a desorption temperature ramp of 18.4° C./min under heliumflow rate of 16 cc/min. The desorbed ammonia and water (if any) weremonitored during the TPAD as meq/g.

Example 1: Synthesis of Zeolite Beta

Eighty (80) parts zeolite beta crystals are combined with 20 partspseudoboehmite alumina, on a calcined dry weight basis. The zeolite betaand pseudoboehmite alumina dry powder are placed in a muller or a mixerand mixed for about 10 to 30 minutes. Sufficient water is added to thezeolite beta and alumina during the mixing process to produce anextrudable paste. The extrudable paste is formed into a 1/20 inchquadrulobe extrudate using an extruder. After extrusion, the 1/20th inchquadrulobe extrudate is dried at a temperature ranging from 250° F.(121° C.) to 325° F. (168° C.). The dried extrudate is then calcined ina nitrogen/air mixture to a temperature between 850° F. (454° C.) and1100° F. (593° C.).

Example 2: Synthesis of EMM-34 Zeolite

Eighty (80) parts EMM-34 zeolite crystals were combined with 20 partspseudoboehmite alumina, on a calcined dry weight basis. The EMM-34 andpseudoboehmite alumina dry powder were placed in a muller or a mixer andmixed for about 10 to 30 minutes. Sufficient water was added to theEMM-34 and alumina during the mixing process to produce an extrudablepaste. The extrudable paste was formed into a 1/20 inch quadrulobeextrudate using an extruder. After extrusion, the 1/20th inch quadrulobeextrudate was dried at a temperature ranging from 250° F. (121° C.) to325° F. (168° C.). After drying, the dried extrudate was heated to 1000°F. (538° C.) under flowing nitrogen. The extrudate was then cooled toambient temperature and humidified with saturated air or steam. Afterthe humidification, the extrudate was ion exchanged with 0.5 to 1 Nammonium nitrate solution. The ammonium nitrate solution ion exchangewas repeated. The ammonium nitrate exchanged extrudate was then washedwith deionized water to remove residual nitrate prior to calcination inair. After washing the wet extrudate, it was dried. The exchanged anddried extrudate was then calcined in a nitrogen/air mixture to atemperature between 850° F. (454° C.) and 1100° F. (593° C.).

Example 3: Synthesis of TEA-Mordenite Zeolite

Eighty (80) parts TEA-mordenite zeolite crystals were combined with 20parts pseudoboehmite alumina, on a calcined dry weight basis. Themordenite and pseudoboehmite alumina dry powder was placed in a mulleror a mixer and mixed for about 10 to 30 minutes. Sufficient water wasadded to the mordenite and alumina during the mixing process to producean extrudable paste. The extrudable paste was formed into a 1/20 inchquadrulobe extrudate using an extruder. After extrusion, the 1/20th inchquadrulobe extrudate was dried at a temperature ranging from 250° F.(121° C.) to 325° F. (168° C.). After drying, the dried extrudate isheated to 1000° F. (538° C.) under flowing nitrogen. The extrudate wasthen cooled to ambient temperature and humidified with saturated air orsteam. After the humidification, the extrudate was ion exchanged with0.5 to 1 N ammonium nitrate solution. The ammonium nitrate solution ionexchange was repeated. The ammonium nitrate exchanged extrudate was thenwashed with deionized water to remove residual nitrate prior tocalcination in air. After washing the wet extrudate, it was dried. Theexchanged and dried extrudate was then calcined in a nitrogen/airmixture to a temperature between 850° F. (454° C.) and 1100° F. (593°C.).

Example 4: Synthesis of Mixed Zeolite Catalyst Composition

EMM-34 and zeolite beta crystals were combined in a number of variousratios with 20 parts pseudoboehmite alumina, on a calcined dry weightbasis. The EMM-34, zeolite beta, and pseudoboehmite alumina dry powderwere placed in a muller or a mixer and mixed for about 10 to 30 minutes.Sufficient water was added during the mixing process to produce anextrudable paste. The extrudable paste was formed into a 1/20 inchquadrulobe extrudate using an extruder. After extrusion, the 1/20th inchquadrulobe extrudate was dried at a temperature ranging from 250° F.(121° C.) to 325° F. (168° C.). After drying, the dried extrudate washeated to 1000° F. (538° C.) under flowing nitrogen. The extrudate wasthen cooled to ambient temperature and humidified with saturated air orsteam. After the humidification, the extrudate was ion exchanged with0.5 to 1 N ammonium nitrate solution. The ammonium nitrate solution ionexchange was repeated. The ammonium nitrate exchanged extrudate was thenwashed with deionized water to remove residual nitrate prior tocalcination in air. After washing the wet extrudate, it was dried. Theexchanged and dried extrudate was then calcined in a nitrogen/airmixture to a temperature between 850° F. (454° C.) and 1100° F. (593°C.).

The zeolites and catalyst compositions materials described above werecharacterized for poison capacity when deployed in a guard bed (GB),such as a reactive guard bed (RGB) or a non-reactive guard bed, duringalkylation service by testing them for their acidity or amount of acidsites. These acid sites are known in the art for providing the poisoncapacity in GB service. One way to measure catalyst acidity is by itsAlpha Value or a standard hexane cracking test. A second way to measureacidity of a material is to determine the total uptake of collidine on amass basis. A third way to measure acidity of a material is to adsorbammonia on the material at a particular temperature, and then determinethe amount of ammonia desorbed from that material as the temperature isincreased.

For the Figures used herein, the composition numbers on the x-axis arethe percentage of a particular zeolite in the formed extrudate. The“linear trend” line is what would be expected if the addition of EMM-34and zeolite beta to the formed extrudate was purely an additive effect.Any deviation from the “linear trend” would be an unexpected result.

Example 5: Performance Testing—Alpha Value

The results of the alpha test in FIG. 1 below show a linear trend linedrawn between a 100 wt. % EMM-34 and 100 wt. % zeolite beta. While the100 wt. % TEA-mordenite and the mixed zeolite 10 wt. % TEA-mordenite/90wt. % zeolite beta essentially fall on the linear trend line, the mixedzeolite combinations of EMM-34 and zeolite beta deviate significantlyfrom the trend line and have higher acidity (and higher hexane crackingactivity). This unexpected result shows a significant advantage for the10 wt. % EMM-34/90 wt. % zeolite beta catalyst composition of mixedzeolite formulation for GB service.

Example 6: Performance Testing—Collidine Uptake

The results of the collidine uptake test in FIG. 2 show a linear trendline drawn between a 100 wt. % EMM-34 and a 100 wt. % zeolite beta.While the 100 wt. % TEA-mordenite and the mixed zeolite 10 wt. %TEA-mordenite/90 wt. % zeolite beta essentially fall on the linear trendline, the mixed zeolite combinations of EMM-34 and zeolite beta deviatesignificantly from the trend line. The unexpected results show that the90 wt. % EMM-34/10 wt. % zeolite beta has a lower collidine uptake,while the 50 wt. % EMM-34/50% zeolite beta and the 10 wt. % EMM-34 and90 wt. % zeolite beta have a higher collidine uptake. This unexpectedresult shows an advantage for the combinations of EMM-34 and zeolitebeta of 50 wt. %/50 wt. % and higher amounts of zeolite beta.

Example 7: Performance Testing—Temperature Programmed Ammonia Desorption

The results of the temperature programmed ammonia desorption (TPAD) testin FIG. 3 show a linear trend line drawn between a 100% EMM-34 and 100%zeolite beta. The EMM-34 has a higher TPAD than does the zeolite betamaterial and thus the linear trend line has a negative slope. In thiscase, the TEA-mordenite has an inherently lower TPAD and thus a second“Mordenite Linear Trend” has been drawn between 100% TEA-mordenite and100% zeolite beta materials that have a positive slope. The mixedzeolite 10% TEA-mordenite/90% zeolite beta material has a TPAD valuethat sits close to the “Mordenite Linear Trend” line. The unexpectedresults show that the 90% EMM-34/10% zeolite beta material has a lowerTPAD, while the 50% EMM-34/50% zeolite beta and the 10% EMM-34 and 90%zeolite beta materials have a higher TPAD. This unexpected result showsan advantage for the combinations of EMM-34 and zeolite beta of 50/50and higher amounts of zeolite beta.

Example 8: Amorphous Silica as Silica Source and TEA-OH as SDA

626.2 g of water was weighed out. 74.5 g of 50 wt. % NaOH and 10.1 g 35wt. % TEA-OH (SDA) was added to the water to form a solution. Thesolution was stirred until the solution was clear. 83.1 g of 27%Al₂(SO₄)₃ was added slowly to the solution. 1.4 g of NaCl was dissolvedin 20 g of water. 7.2 g of zeolite beta seeds were added to thesolution. The solution was mixed for 5-10 minutes. 186.5 g of amorphoussilica (Hi-Sil 233™, obtainable from PPG) was added slowly to thesolution to form a slurry. 322.6 g of 50 wt. % TEA-Br and the NaClsolution was added to the slurry to form a gel. The gel was thoroughlymixed prior to charging to a stirred autoclave, and stirred at 250 rpmat 140° C. for 120 hours. The nominal gel molar composition parameterswere as follows:

SiO₂/Al₂O₃=41.38

Na (Alkali)/SiO₂=0.34

SDA/SiO₂=0.29

OH—/SiO₂=0.35

H₂O/SiO₂=18.84

The X-ray diffraction (XRD) pattern, as shown in FIG. 4, indicates thatthe product that was isolated from the autoclave was a mixture ofzeolite beta and mordenite where the amount of zeolite beta in theproduct was approximately 6%. After pre-calcination, ammonium ionexchange, and calcination at 550° C. the collidine uptake was 367μmoles/g.

Example 9: Precipitated Silica as Silica Source, TEA-BR as SDA,TEA/Na=0.899

74.6 g of 50 wt. % NaOH was diluted in 641.5 g of water. The solutionwas stirred until it was clear. 84.2 g of 27% Al₂(SO₄)₃ solution wasslowly added to the hydroxide solution. 7.3 g of zeolite beta seeds wasadded to the solution, and mixed for 5-10 minutes. 175.9 g of aprecipitated silica (Ultrasil PM modified silica, obtainable fromEvonik) was slowly added to the solution to form a slurry. 352.8 g of 50wt. % TEA-Br was added to the slurry to form a gel. The gel wasthoroughly mixed prior to charging to a stirred autoclave, and stirredat 250 rpm at 140° C. for 120 hours. The nominal gel molar compositionparameters were as follows:

SiO₂/Al₂O₃=40.7

Na (alkali)/SiO₂=0.343

SDA/SiO₂=0.305

TEA/Na=0.899

OH⁻/SiO₂=0.343

H₂O/SiO₂=18.95

The XRD pattern, as shown in FIG. 5, indicates that the product that wasisolated from the autoclave was a mixture of zeolite beta and mordenitewhere the amount of zeolite beta in the product was approximately 60%.

Example 10: Precipitated Silica as Silica Source, TEA-BR as SDA,TEA/Na=1.11

74.1 g of 50 wt. % NaOH was diluted in 647.5 g of water. The solutionwas stirred until it was clear. 84.8 g of 27% Al₂(SO₄)₃ solution wasadded slowly to the hydroxide solution. 6.7 g of zeolite beta seeds wasadded to the solution. The solution was mixed for 5-10 minutes. 177.0 gof a precipitated silica (Ultrasil PM modified silica, obtainable fromEvonik) was slowly added. 351.2 g of 50 wt. % TEA-Br was added to form agel. The gel was mixed thoroughly prior to charging to a stirredautoclave, and stirred at 250 rpm at 140° C. for 120 hours. The nominalgel molar composition parameters were as follows:

SiO₂/Al₂O₃=40.7

(Na) alkali/SiO₂=0.338

SDA/SiO₂=0.305

TEA/Na=1.11

OH⁻/SiO₂=0.338

H₂O/SiO₂=18.95

The XRD pattern, as shown in FIG. 6, indicates that the product that wasisolated from the reaction mixture was a mixture of beta and mordenitewhere the amount of beta in the product was approximately 92%. Afterpre-calcination, ammonium ion exchange, and calcination at 550° C. thecollidine uptake was 575 μmoles/g.

Example 11: Precipitated Silica as Silica Source, TEA-OH and TEA-BR asSDA

54.1 g of 50 wt. % NaOH was added to 646.5 g of water to form a NaOHsolution. 89.3 g of 35 wt. % TEA-OH (SDA) was added to the NaOHsolution. While agitating the NaOH solution, 85.2 g of 47% Al₂(SO₄)₃ wasadded. 7.4 g of zeolite beta seeds was added. 178.0 g of a precipitatedsilica (Ultrasil PM modified silica, obtainable from Evonik) was slowlyadded to the solution. 267.6 g of 50% TEA-Br (SDA) was added and mixedfor 30 minutes prior to charging the gel to the autoclave which wasstirred at 250 rpm at 140° C. for 120 hours. The nominal gel molarcomposition parameters were as follows:

SiO₂/Al₂O₃=40.7

(Na) alkali/SiO₂=0.12

SDA/SiO₂=0.31

OH⁻/SiO₂=0.20

H₂O/SiO₂=18.51

The XRD pattern, as shown in FIG. 7, indicates that the product that wasisolated from the autoclave was zeolite beta with no mordeniteimpurities where the amount of zeolite beta in the product wasapproximately 100%. After pre-calcination, ammonium ion exchange, andcalcination at 550° C. the collidine uptake is approximately 700μmoles/g.

Certain embodiments and features have been described using a set ofnumerical upper limits and a set of numerical lower limits. It should beappreciated that ranges from any lower limit to any upper limit arecontemplated unless otherwise indicated. Certain lower limits, upperlimits and ranges appear in one or more claims below. All numericalvalues take into account experimental error and variations that would beexpected by a person having ordinary skill in the art.

Various terms have been defined above. To the extent a term used in aclaim is not defined above, it should be given the broadest definitionpersons in the pertinent art have given that term as reflected in atleast one printed publication or issued patent. Furthermore, allpatents, test procedures, and other documents cited in this applicationare fully incorporated by reference to the extent such disclosure is notinconsistent with this application and for all jurisdictions in whichsuch incorporation is permitted.

The foregoing description of the disclosure illustrates and describesthe present disclosure. Additionally, the disclosure shows and describesonly the preferred embodiments but, as mentioned above, it is to beunderstood that the disclosure is capable of use in various othercombinations, modifications, and environments and is capable of changesor modifications within the scope of the concept as expressed herein,commensurate with the above teachings and/or the skill or knowledge ofthe relevant art.

1. A catalyst composition comprising a first zeolite having a BEA*framework type and a second zeolite having a MOR framework type and amesopore surface area of greater than 30 m²/g as measured by BET.
 2. Thecatalyst composition of claim 1, wherein said first zeolite is zeolitebeta.
 3. The catalyst composition of claim 1, wherein said secondzeolite is EMM-34.
 4. The catalyst composition of claim 3, wherein saidsecond zeolite comprising agglomerates of primary crystallites, whereinsaid primary crystallites have an average primary crystal size of lessthan 80 nm in each of the a, b and c crystal vectors as measured byX-ray diffraction and an aspect ratio of less than 2, wherein the aspectratio is defined as the longest dimension of the crystallite divided bythe width of the crystallite, wherein said width of the crystallite isdefined as the dimension of the crystallite in the middle of thatlongest dimension in a direction orthogonal to that longest dimension,as measured by TEM.
 5. The catalyst composition of claim 4, wherein saidEMM-34 has a ratio of the mesopore surface area to the total surfacearea of greater than 0.05.
 6. The catalyst composition of claim 5,wherein said second zeolite is synthesized from TEA or MTEA.
 7. Thecatalyst composition of claim 6, wherein the Si/Al₂ molar ratio of saidsecond zeolite is in the range of 10 to
 60. 8. The catalyst compositionclaim 7, wherein said catalyst composition has a collidine uptake in therange of 550 μmoles/g to 1500 μmoles/g.
 9. The catalyst composition ofclaim 8, wherein the ratio of said first zeolite to said second zeoliteis in the range of 90:10 to 50:50 by weight of the catalyst composition.10. The catalyst composition of claim 9, wherein said first zeolite andsaid second zeolite are co-crystallized or co-extruded.
 11. A method forremoving impurities from a hydrocarbon stream, the method comprising thesteps of: (a) supplying a portion of a feed stream and a guard bedcatalyst, said feed stream comprising one or more hydrocarbons andundesirable impurities, said impurities comprise at least one compoundhaving at least one of the following elements: nitrogen, halogens,oxygen, sulfur, arsenic, selenium, tellurium, phosphorus, and Group 1through Group 12 metals, said guard bed catalyst comprises a catalystcomposition of claim 1; and (b) contacting said portion of said feedstream with said guard bed catalyst to remove at least a portion of saidimpurities and produce a treated feed stream having a reduced amount ofimpurities.
 12. The method of claim 11, wherein said feed stream andsaid guard bed are supplied to a guard bed for contacting therein.
 13. Aprocess for producing a mono-alkylated aromatic compound comprising thesteps of: (a) providing a guard bed having a guard bed catalyst disposedtherein, said guard bed catalyst comprises a catalyst composition ofclaim 1; (b) supplying at least a portion of an untreated feed stream tosaid guard bed, said untreated feed stream comprising an alkylatablearomatic compound and undesirable impurities, wherein said impuritiescomprise at least one compound having at least one of the followingelements: nitrogen, halogens, oxygen, sulfur, arsenic, selenium,tellurium, phosphorus, and Group 1 through Group 12 metals; (c)contacting said portion of said untreated feed stream of step (b) withsaid guard bed catalyst to remove at least a portion of said impuritiesand produce a treated feed stream having a reduced amount of impurities;and (d) contacting at least a portion of said treated feed stream ofstep (c) and an alkylating agent stream with an alkylation catalystwhich is the same or different from said guard bed catalyst undersuitable at least partially liquid phase reaction conditions to alkylateat least a portion of said alkylatable aromatic compound with saidalkylating agent stream to produce an effluent stream comprising saidmono-alkylated aromatic compound and poly-alkylated aromatic compounds.14. The process of claim 13, wherein step (b) further includes supplyingan alkylating agent stream to said guard bed.
 15. The process of claim14, wherein step (c) further includes contacting said alkylating agentstream with said alkylatable aromatic compound in the presence of saidguard bed catalyst to produce additional said mono-alkylated aromaticcompound.
 16. The process of claim 15, wherein said alkylation catalystcomprises an acidic aluminosilicate.
 17. The process of claim 16,wherein said aluminosilicate is any one of a MCM-22 family molecularsieve, faujasite, mordenite, zeolite beta, or combinations of two ormore thereof.
 18. The process of claim 17, wherein said MCM-22 familymolecular sieve is any one of MCM-22, PSH-3, SSZ-25, MCM-36, MCM-49,MCM-56, ERB-1, EMM-10, EMM-10-P, EMM-12, EMM-13, UZM-8, UZM-8HS, UZM-37,ITQ-1, ITQ-2, ITQ-30, MIT-1, or combinations of two or more thereof. 19.The process of claim 18, further comprising the steps: (e) separatingsaid effluent stream of step (d) to recover a mono-alkylated aromaticcompound stream and a poly-alkylated aromatic compounds stream.
 20. Theprocess of claim 19, further comprising the step of: contacting saidpoly-alkylated aromatic compound stream and another portion of saiduntreated feed stream of step (b) with a transalkylation catalyst undersuitable at least partially liquid phase transalkylation conditions totransalkylate said poly-alkylated aromatic compound stream with saidalkylatable aromatic compound and produce additional said mono-alkylatedaromatic compound.
 21. The process of claim 20, wherein prior to step(f) said another portion of said untreated feed stream is firstcontacted with a guard bed catalyst to remove at least a portion of saidimpurities, said guard bed catalyst comprises a catalyst composition ofclaim
 1. 22. The process of claim 20, wherein said transalkylationcatalyst is a large pore molecular sieve having a constraint index ofless than 2 or a MCM-22 family material.
 23. The process of claim 22,wherein said large pore molecular sieve is selected from the group ofconsisting of zeolite beta, faujasite, zeolite Y, Ultrastable Y (USY),Dealuminized Y (Deal Y), Rare Earth Y (REY), Ultrahydrophobic Y (UHP-Y),mordenite, TEA-mordenite, EMM-34, ZSM-2, ZSM-3, ZSM-4, ZSM-14, ZSM-18,ZSM-20, ECR-4, ECR-17, ECR-32, ECR-35 and combinations thereof.
 24. Theprocess of claim 13, wherein said alkylatable aromatic compound isbenzene, said mono-alkylated aromatic compound is ethylbenzene and saidpoly-alkylated aromatic compound is poly-ethylbenzene.
 25. The processof claim 13, wherein said alkylatable aromatic compound is benzene, saidmono-alkylated aromatic compound is cumene and said poly-alkylatedaromatic compound is poly-isopropylbenzene.